Up in their cloud condo complex, the Birdtaurs have been obsessively watching the herd: Horse and friends are their favorite reality stars!

Horse meets Waterbaby — one of Centaurworld's shamans — and learns about the key: a mysterious object that could reunite her with Rider.

The group follows the Rainbow Road into a deep, dark hole, where a Moletaur locks them in jail and informs them that they'll face the judge.

Horse hopes to find the final shaman in Merfolk Town. But she's growing discouraged — and looking more and more like a centaur every day.

The herd sets out to find the way home. Wammawink encourages them to be careful and take it slow, but fearless Horse charges ahead.

Horse tries to recruit an army to defend Centaurworld, but no one wants to join. The herd visits the Horsetaurs' castle to see if they'll help.

The friends seek shelter in a cave during a storm... but they're not alone. While looking for an exit, they discover strange paintings on the walls.

Horse tries to enlist the fierce Coldtaurs in her battle — but they capture Glendale! Back in the human world, Waterbaby sends a message to Rider.

On a trip to the Underground Kingdom, Horse learns that Rider has a magnificent new horse named Becky Apples. Would Rider really replace her?

Searching for the next piece of the key, Horse leads the herd into a mysterious forest to see the tree shamans. They grant wishes — but there's a catch.

All of Centaurworld's residents gather for the hootenanny. But can Horse turn this colorful collection of creatures into a fearless army?

Separated from her Rider during battle, Horse wakes up in a colorful world filled with strange beasts. But where is her trusty friend?

Rider defies the general's orders and goes to the Nowhere King's castle to get the artifact. But her new horse, Becky Apples, isn't exactly cooperative.

Zulius brings the herd to Cataur Valley, where the shaman is fuzzy but fierce. To earn a piece of the key, Horse goes glam for a silly competition.

Horse discovers a powerful ability: She can jump into backstories! And seeing the tough times her herd friends faced helps her feel less alone.

The herd makes it to the Rift and reminisces about their time together while waiting for Waterbaby to arrive with the final piece of the key.

Horse and Rider face a frightening enemy. Back in Centaurworld, the herd summons up the courage to enter the void and fight for their friend.

Horse leaps into the Nowhere King's mind and learns his haunting backstory. Meanwhile, Rider and the herd come up with a plan.